Grating and method of making same



Feb 25 1936. w. P. LADD GRAT ING 'AND METHOD OF MAKING SAME Filed June 29, 1935 2. Sheets-Sheet l Illllllz JZUGW' Waiter Pia/dd,

lunimuiuIuumInunummimimiii Patented Feb. 25 1936 UNITED STATES PATENT OFFICE 13 Claims.

The present invention relates to gratings and methods of making the same.

More particularly the present invention relates to improvements in gratings made up of bars, a series of spaced parallel main bars having operatively associated therewith a series of spaced parallel cross bars, the first mentioned bars and the cross bars being so interlocked as to form a rigid grating.

V An object of the present invention is to provide a grating which may be made up of simple parts readily purchasable in the open market, which is cheap to manufacture, and rigid in construction.

V A further object is to provide a grating in which the cross bars are so interlocked with the main bars that they form effective knee braces between said main bars.

A further object is to provide an improved grat- 20 mg in which portions of the cross bars are in such tight fitting relationship with the main bars that a structure of improved rigidity results.

A further object is to provide a simple and inexpensive method of making a grating which will result in a rigid'structure.

Other' objects will appear as the description proceeds;

Referring to the drawings:

Figure 1 is a view in perspective of a -portion of 301 agrating embodying the principles of the present invention;

Figure 215 a View in side elevation of a section of a top die member which may be, used' in' the p racticeof the present invention;

Figure3 is a view in side elevation of a section of a'b'ottomdie member which may be used in the practice of the present invention, employing a plurality of sections such as shown in Figure'2;

Figure 4 is a view in front elevation of a top die member employing a plurality of sections'such as shown in Figure 2;

Figure 5 is aview'in front elevation of a bottom die member employing a plurality of sections such initial steps of forcing said main and cross bars into cooperative relationship with each other;

Figure 9 is a view somewhat similar to Figure 8 but showing the top die member at the end of its stroke at which time the cross bar member has 5 been forced into cooperative relationship with a main member; and

Figure 10 is a sectional view of a finished grat ing, the view being taken in the direction of the arrows Iii-J0 of Figure 9.

The illustrated embodiment of the present invention includes the main members I II I which comprise flat bars having slots I2I2 therein,- which slots communicate with the upper edges of said bars II. Said slots I2I2 at their inner extremities have their axes inclined relative to the length of the bar II as indicated by the numerals I4I4. Expressed in other language, the slots I2--I2 throughout a portion of their length have parallel spaced walls intersecting the upper edges of the main bar II. Said parallel walls of the slots II--II at the lower extremities of said slots are bent or inclined relative to the length of the bar. Disposed within the slots I2--I2 of the main bars I I are the cross bars I5-I 5. At the beginning of operations, said cross bars I5I5 may be imperforate, as illustrated in Figure '7. However, as will be explained as the description proceeds, when said cross bars I5-I5 are forced down into the slots I2-I 2 of the main bars I I'-I I the lower edges of said bars I5I 5 will be sheared, and preferably those portions of the lower edge of theicross bars I5I5 which are located between the main bars I I---! I will be swedged ina directionopposite to the inclination ofthe lower extremities I4I4 of the slots I2-I2, whereas those portions of the lower edges of the cross bars I5-I5 which lie between the two sides of each main bar I I are swedged down into the extremities I I-I4 of the slots I2-I2. ferred to of the cross bars I5-'I5 which lie between the main bars I I-II are indicated by the numerals I6I6 whereas'those portions of the cross bars I5I5 which lie between the sides of each main bar' II are indicated by the numerals H. The portions I6--I 6 are upset during the operation of forcing the cross bars I5I5 down into the slots I2 whereby said portions I6-I6 are forced into rigid relationship with the main bars I I--I I, acting as knee braces between said main bars'I II I. I

An upper die member which may be used in the practice of the present invention is indicated by the numeral I8 and is illustrated in Figure 4.

A lower die member which may be used in the The portions re- 40 practice of the invention is indicated by the numeral l9 and illustrated in Figure 5. The member |8 has secured to its underface a plurality of spaced die sections 2020. Said die sections 20-20 are spaced apart a distance sufficient to snugly receive the main bars The bottom die member I9 is provided with a plurality of spaced die sections 2|2| which coincide in position with the upper die sections 2020, being also spaced apart a distance to snugly receive the main bars As shown in Figures 2 and 8 each die section 20 is provided on its lower face with a pair of teeth 22 and 23 which teeth are spaced apart a sufficient distance to snugly receive a cross bar I5. The upper face of each lower die section 2| is provided with a tooth 24 having a vertical side wall 25 disposed in the same vertical plane with the inner face of the tooth 23. The tooth 24 is provided with the inclined wall 26 which intersects the vertical wall 25. The inclined wall 26 has the function of swedging the portions |6-|6 of the cross bars |5|5 into their inclined positions, as shown in Figures 1 and 9.

In operation a set of main bars will be disposed between the sections 2020 of the upper die member l8 and between the sections 2 |2|of the lower die member l8. As shown in Figure 8 the die sections 20 and 2| will be spaced apart a sufficient distance to allow said main members to be positioned between said sections 20 on the top side, and the sections 2| on the lower side. The slots |2|2 in the various main bars I will be coincident with one another and said slots, in succession, will be disposed in coincidental relationship with the space between the teeth 22 and 23 of the upper die sections 20. Mechanism for moving the main bars in unison into proper relationship with the upper and lower die members will occur to those skilled in the art and no description of such moving means is deemed to be necessary in this specification. With the upper die sections 20, the lower sections 2|, and the main bars II in the positions referred to, which positions are illustrated in Figure 8, the cross bar l5 will be inserted between the teeth 22 and 23 of each of the upper die sections 20, said cross bar I5 contacting with the wall 25 of the tooth 24 of each lower die section 2|. With the cross bar I5 in the position described, the requisite force will be applied to the upper die member l8 to force the cross bar l5 down into the main bars The inclined walls 2626 of the teeth 24 of the lower die sections 2| will shear the lower edge of the cross bar |5 along lines coincidental with the side faces of the main bars the portions |6|6 between the main bars being swedged in one direction by the walls 26-46 of the lower die sections 2|-2|, the portions ll lying between the side faces of each main bar being forced down into the portions |4|4 of the slots l2, whereby to be inclined oppositely to the portions |6|6. The upper die member l8 will be forced down a sufficient distance to bring the upper edge portions of the cross bars |5 into the desired relationship with the main bars the slots |2|2 being designed to be completely filled with the portions of the cross bars l5|5 when the proper level of the cross bars |5|5 relative to the main bars has been attained.

During the operation of forcing the cross bar I5 down into the aligned slots |2|2 of the main bars ll-l the portions |6-| 6 by reason of their engagement with the inclined walls 2626 of the lower die sections 2|-2| will be upset, whereby the length of said portions |6--|6 between the main bars I will tend to increase and the ends of said portions Iii-l5 will be forced into intimate bearing relationship with the side faces of the main bars to act as eifective knee braces. It will be understood, of course, that if'a further upsetting action be desired beyond that accomplished by the friction between the inclined walls 26-26 and the lower edge of the cross bar IS, an abutment may be provided to stop the movement of the metal comprising the portion |6--|B of the cross bar l5 as it is forced home whereby to spread said metal into intimate relationship with the side faces of the main bars |l| Though a preferred embodiment of the present invention has been described in detail, many modifications will occur to those skilled in the art. It is intended to cover all such modifications which fall within the scope of the appended claims.

' What is claimed is 1. A grating comprising a plurality of spaced parallel main bars having slots therein communicating with their edges and cross bars disposed within said slots, each of said cross bars having portions turned from the plane of said cross bar and abutting adjacent side faces of adjacent main bars.

2. A grating comprising a plurality of spaced parallel main bars having slots therein communicating with their edges and cross bars disposed within said slots, each of said cross bars having portions turned from the plane of said cross bar and abutting adjacent side faces of adjacent main bars, said portions being upset to contact intimately with said adjacent faces.

3. A grating comprising a plurality of parallel spaced main bars having edges thereof disposed in a singleplane and having slots communicating with said coplanar edges, cross bars disposed within said slots, each of said cross bars having portions turned from the plane of said cross bars and abutting adjacent side faces of adjacent main bars.

4. A grating comprising a plurality of parallel spaced main bars having edges thereof disposed in a single plane and. having slots communicating with said coplanar edges, cross bars disposed within said slots, each of said cross bars having portions turned from the plane of said cross bars to provide braces between said main bars, said turned portions being upset whereby to intimately contact with adjacent faces of adjacent main bars.

5. A grating comprising, in combination, a plurality of parallel spaced main bars having edges thereof in a single plane, said bars having slots communicating with said coplanar edges, said slots having a portion normal to said plane and a portion in angular relationship with said plane, and cross bars disposed within said slots, portions of said cross bars between said main bars being turned oppositely to the angular portions of said slots. 7

6. A grating comprising, in combination, a plurality of parallel spaced main bars having edges thereof in a single plane, said bars having slots communicating with said coplanar edges, said slots having a portion normal to said plane and a portion in angular relationship with said plane,

and cross bars disposed within said slots, portions of said cross bars between said main bars being turned oppositely to the angular portions of said slots, said turned portions of said cross bars being swedged into intimate relationship with adjacent side faces of adjacent main bars.

7. A grating comp-rising main bars and transverse b-ars, said main bars having slots, said slo ts having their extremities turned at an angle to the other portions of said slots, said transverse bars being disposed within said slotsincluding the extremities thereof, said transverse bars having portions turned intermediate of adjacent faces of adjacent main bars and abutting said adjacent side faces of said adjacent main bars to provide knee braces between said main bars.

8. A grating comprising main bars and transverse bars, said main bars having slots, said slots having their extremities turned at an angle to the other portions of said slots, said transverse bars being disposed within said slots including the extremities thereof, said transverse bars having portions turned intermediate of adjacent faces of adjacent main bars to provide knee braces between said main bars, the angle of turning of said portions being reverse to the angle of the extremities of said slots.

9. A grating comprising main bars and transverse bars, said main bars having slots, said slots having their extremities turned at an angle to the other portions of said slots, said transverse bars being disposed within said slots including the extremities thereof, said transverse bars having portions turned intermediate of adjacent faces of adjacent main bars to provide knee braces between said main bars, said turned portions being upset whereby to engage intimately with adjacent faces of said adjacent main bars.

10. A grating comprising main bars and transverse bars, said main bars having slots, said slots having their extremities turned at an angle to the other portions of said slots, said transverse bars being disposed within said slots including the extremities thereof, said transverse bars having portions turned intermediate of adjacent faces of adjacent main bars to provide knee braces between said main bars, the angle of turning of said portions being reverse to the angle of the extremities of said slots, said turned portions being upset whereby to engage intimately with adjacent faces of said adjacent main bars.

11. The method of making a grating which comprises providing main bars in spaced parallel relationship with their edges coplanar, said main bars having slots communicating with said coplanar edges, forcing transverse bars into said slots and shearing and turning portions of said transverse bars into angular relationship with said transverse bars between said main bars.

12. The method of making a grating which consists of providing a set of parallel spaced main bars having edges in a single plane, said main bars having slots communicating with said coplanar edges, each of said slots having its inner extremity turned in angular relationship with the remainder of said slot, forcing transverse bars into said slots, and during said forcing operation, shearing and turning portions of said transverse bars between said main bars into angular relationship with said extremities.

13. The method of making a grating which consists of providing a set of parallel spaced main bars having edges in a single plane, said main bars having slots communicating with said coplanar edges, each of said slots having its inner extremity turned in angular relationship with the remainder of said slot, forcing transverse bars into said slots, and during said forcing operation shearing and upsetting portions of said transverse bars between said main bars, and during said shearing operation turning said last mentioned portions into angular relationship with said extremities.

WALTER P. LADD. 

